By the end of this storyboard I aim to convince you, the viewer, on just how effective good visualisations can be in conveying deep messages and ideas about complex or overwhelming amounts of data.
We will be using the freely available gapminder data set to explore how long people are living on average across various countries around the globe.
This data set contains 1704 observations spanning the years 1952 - 2007.
A total of 142 countries are represented in this data set.
As you can see, this data set contains observations for other interesting statistics for countries, like population size and GDP per capita.
We won’t be focusing on these stats in our visualisations.
This is a histogram showing the distribution of life expectancy across the world at each year that was collected from contributing countries.
Notice how the distribution slowly creeps to the right, implying more countries are having longer life expectancies.
Does this suggest the straightforward and succinct answer of: yes, we are living longer now then in the recent past. Or is there more to the story?
Let’s look at the data another way.
This represents a linked chart for the life expectancy of each country over time on the left, and their location on the world map to the right.
Selecting a color and country will highlight that countries specific chart line and location on the map.
The gold line represents the country that is most improved over the entire year range, while the brown lines represent the worst performing countries over the same interval.
Overall, it appears that many countries have improved their citizen life expectancy since 1952, as seen by the general positive trend for most lines and the heavier clustering of lines in 2007 around the 65 to 80 yr range.
However, there are three distinct troughs in the 60s,70s and 90s, with a noticeable downward turn for a number of countries starting in the mid-late 80s.
World shape file sourced here.
This is a graph of the average life expectancy on each continent (calculated from a population size weighted average of the life expectancy of each country in a continent/region).
Oceania, Europe and the Americas show a consistent and steady rise in their respective life expectancy over this time period.
After an early blip, attributable to some degree to the previously mentioned historical events in China and Cambodia, Asia follows an equally steady climb.
Africa starts well in improving its life expectancy but then platues around the late 80s.
Of the 52 African countries included in this data set, 28 of them have a noticeable downward trend starting in the late 80s or early 90s.
The most unique and prominent of these dips is seen in Rwanda. Unlike the other 27 regressing countries, Rwanda exhibits a steep drop off with an almost elastic and rapid relative recovery.
This coincides with the Rwandan Civil War from 1990 - 1994.
Africa shape file sourced here.
This a map of all the African countries who showed a steady decline in life expectancy from the early 1990s. (Note: Click on the multiple pages icon on upper left of chart area to filter choropleth)
Most of these countries would be considered part of the Sub-Saharan grouping of African countries.
This correlates with the stats from a UNAIDS organisation fact sheet, which describes how 64% of the global HIV prevalence was found in Sub-Saharan Africa by 2005.
Some of these countries peaked in HIV infection rates around the 1990s, where anti-retroviral therapy was not easily available.
This downward trend of life expectancy observed in these countries during this time, corresponds well with the HIV pandemic during the 1990s and 2000s.
Estimates for HIV prevalence in Sub-Saharan African countries in 2001 sourced here
In the next two animations, the aim is to appreciate the dynamic movement of life expectancy across countries through time.
As we learnt from our previous observations, Europe, Oceania and the Americas have consistently improved their life expectancy over this time range.
Looking at Africa and Asia, both overlaped closely in terms of life expectancy in 1952.
Both regions showed improvement until the late 1980s.
However, after this point in time, Asia continued to improve while Africa shows a clear seperation and regression in life expectancy.
This is depicted on the chart by the plummeting bubbles representing African countries, starting around the 1990s.
From the previous animation, we noted how Africa seemed to rapidly fall off in terms of life expectancy in and around the 1990s.
However, focusing in on the African continent, not all countries show this behaviour.
In fact, most of the North African countries follow the trend of the rest of the world, which is ever increasing life expectancy over this time period.
It is the Sub-Saharan countries that showcase the noticeable decline, with the association to the emerging HIV pandemic being a strong candidate for this.
In short, it appears most of the world is living longer now compared to the past, except for certain parts of Africa.
This chart depicts South Africa’s estimated life expectancy for years 1952 till 2007 (in 4 year intervals) and yearly estimates from 2008-2018.
The gapminder data set provided data from before 2007, while estimates from 2008 was soruced from The World Bank, available here
The blue line represents the observed estimates, while the orange ribbon represents the projected life expectancy for the next two 4 year intervals (in keeping with the way that the gapminder data set recorded its data).
From this, it is clear that South Africa has not only done well to improve its citizens’ life expectncy, but also to exceed forecasted expectations of life expectancy beyond 2007.
This drastic change in outlook coincides well with the mass rollout of anti-retroviral agents and improved HIV and related issues care throughout South Africa in the mid-late 2000s.